Alright who stole the stars

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Came across this interesting article about disappearing stars, there one minute gone the next. Curious to know is this in the same region of our galaxy or all over didn’t notice in the article that stated this?

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Came across this interesting article about disappearing stars, there one minute gone the next. Curious to know is this in the same region of our galaxy or all over didn’t notice in the article that stated this?

It says "the naval catalogue spans around 50 years of sky surveys, capturing details of the entire sky." So I would assume that they are distributed throughout the sky. It would be remarkable if they had all been in the same location, so I imagine that would have been mentioned if that were the case.

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It says "the naval catalogue spans around 50 years of sky surveys, capturing details of the entire sky." So I would assume that they are distributed throughout the sky. It would be remarkable if they had all been in the same location, so I imagine that would have been mentioned if that were the case.

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It's random locations from what I could gather from the article. Keep in mind they are examining old images from the 50's. They do mention the possibility of scratches being one cause. Ie some of the supposed stars may not have existed. Ideally I hope they get other image samples from the same Era and run comparisons.

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It's random locations from what I could gather from the article. Keep in mind they are examining old images from the 50's. They do mention the possibility of scratches being one cause. Ie some of the supposed stars may not have existed. Ideally I hope they get other image samples from the same Era and run comparisons.

Thank you

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It's random locations from what I could gather from the article. Keep in mind they are examining old images from the 50's. They do mention the possibility of scratches being one cause. Ie some of the supposed stars may not have existed. Ideally I hope they get other image samples from the same Era and run comparisons.

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That is not how I interpret the article. It says the stars are missing from data that dates back to the 1950s.

Quote

By comparing star catalogues dating back to the 1950s with more recent datasets, researchers with the Vanishing & Appearing Sources during a Century of Observations project have identified around 100 bright dots that seem to have vanished without a trace.

I found the following passage interesting, it's from the abstract for the paper that the above article is based upon. The missing stars seems to have certain properties. I do not know what this implies (yet).

Quote

We show that these objects are redder and have larger proper motions than typical USNO objects. We visually examine the images for a subset of about 24,000 candidates, superseding the 2016 study with a sample 10 times larger. We find about 100 point sources visible in only one epoch in the red band of the USNO, which may be of interest in searches for strong M-dwarf flares, high-redshift supernovae, or other categories of unidentified red transients.

I found the following passage interesting, it's from the abstract for the paper that the above article is based upon. The missing stars seems to have certain properties. I do not know what this implies (yet).

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"there one minute gone the next". Since the observations that were compared could be performed decades apart the vanishing objects could have dimmed over several years or moved to another location. Not necessarily disappeared from one minute to the next as a fick of a switch.

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"there one minute gone the next". Since the observations that were compared could be performed decades apart the vanishing objects could have dimmed over several years or moved to another location. Not necessarily disappeared from one minute to the next as a fick of a switch.

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Good point. I guess the author of the article meant one moment from a cosmological perspective.

From the paper:

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Using a relatively large time window of ∼ 70 years, in combination with a large sample size, increases the probability of finding extremely rare events. Clearly this is still a minute time duration from a cosmological perspective, but it nevertheless sets an upper limit on the incidence of vanishing or appearing-star events.

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For some of those classes of transients, I would have thought you would also expect to see some objects in the new data set that were not there in the earlier one.

Yes, it is in the title of the project: THE VANISHING & APPEARING SOURCES DURING A CENTURY OF OBSERVATIONS PROJECT (VASCO).

I suppose (I couldn't spot this in the paper) that since observation technology is steadily improving through time, the discovering of a new (faint) object is not impressive. The vanishing object is much more unexpected.

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But It could be interesting if there are objects bright enough that they should have been in the older photos.

I agree, we just have to wait for the next report

(emphasis mine)

Quote

5.3.2. Expanding the set of candidates

What we have presented so far is a cross-match be- tween USNO and Pan-STARRS in searches for vanishing objects, using a 30 arcsec cross-match radius. However, the plan of VASCO is to do the following:

Finalize the current search for vanishing objects with a 30 arcsec cross-match radius by examining the entire Mismatch Sample visually and finalize the cross-match over the sky regions that so far have not been used.

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Sorry got a little confused here , so are these stars just disappearing from the skies?

It is not yet known if stars were disappearing:

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At present, we do not know what these detections represent. We believe they may be a mixed bag of transient phenomena. The object found by Villarroel et al. (2016) is of the same class, and might possibly be a variable object that dropped 4.5 mag since it was imaged long ago. It could also have been some type of transient event such as a background high-redshift supernova or a flaring M dwarf.

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Anyway, galaxies were originally mistaken for stars, I believe. And some or all of the images we're talking about must have been captured using out of date equipment, given their age, so not the best quality. Could gravitational lensing then explain this, duplication of galaxies mistaken for stars or perhaps simply copies of stars in the Milky Way? Fingers crossed this is not the work of ETs seeking to harness the energy of all the stars in the MW as the Sun could be next! The idea that they might be doing it to cover up evidence of their existence seems rather odd to me; what could be more conspicuous than a star that suddenly and inexplicably vanishes?

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What is the idea here. Galaxies were previously mistaken for stars, and now they are "missing" because no stars are left in their places, only galaxies? If you go "oh, there is no star left in this location, only a galaxy", is it not too much of a giveaway that maybe it wasn't a star to begin with?